SYNDAX PHARMACEUTICALS INC

Ticker: SNDX CUSIP: 87164F105 Class: Common Stock

EcoR1 Capital, LLC's Holding History (CIK: 0001587114)

Note: Option positions (PUT/CALL) are excluded.

Q1 2017

Shares 35,301 Value ($000) $484 Avg Close $10.38 Range $6.31 - $15.70

Q4 2016

Shares 273,862 Value ($000) $1,964 Avg Close $10.96 Range $6.69 - $16.40

Q3 2016

Shares 357,365 Value ($000) $5,418 Avg Close $13.15 Range $9.60 - $18.03

Q2 2016

Shares 357,365 Value ($000) $3,520 Avg Close $13.71 Range $8.97 - $17.49

Q1 2016

Shares 510,829 Value ($000) $6,804 Avg Close $12.54 Range $10.60 - $16.30

Period	Shares	Value ($000)	Average Close	Price Range
Q1 2017	35,301	$484	$10.38	$6.31 - $15.70
Q4 2016	273,862	$1,964	$10.96	$6.69 - $16.40
Q3 2016	357,365	$5,418	$13.15	$9.60 - $18.03
Q2 2016	357,365	$3,520	$13.71	$8.97 - $17.49
Q1 2016	510,829	$6,804	$12.54	$10.60 - $16.30